Disposable, absorbent articles typically include a thin, flexible, liquid-impermeable backsheet, an absorbent pad or panel on the backsheet, and an overlying, liquid-permeable topsheet. Each of these components can be typically supplied in the form of a continuous web by an apparatus which forms, guides, combines, and secures the components together.
In addition, some types of disposable, absorbent articles, such as diapers, typically include other components, such as elastic bands in the crotch area of the article to provide enhanced containment and leakage-resistance. Other features may include adhesive-coated tape tabs for securing the article to the wearer, a landing zone target tape against which the tape tabs can be securely, yet removably applied, and front and rear waist elastic elements to provide enhanced fit and comfort.
While a variety of different mechanisms have been developed for combining the above-discussed components to form a completed article, it is preferable to employ such mechanisms along a processing line controlled operation together to fabricate the article on a continuous basis as the major components move along the processing line.
It is also desirable to operate an absorbent article manufacturing line at relatively high speeds so as to produce completed articles at a relatively high production rate. Depending upon the nature of the article, and upon the number of features in the article, manufacturers may attempt to achieve production rates on the order of hundreds of units per minute. When absorbent article component assembly mechanisms are operated at high speeds, the proper component processing operations, such as registration, cutting, bonding, etc., become more difficult.
These processing problems are exacerbated by the fact that absorbent articles are typically fabricated from continuous webs of material which are assembled on a continuously moving basis along the length of the articles while some discrete components of other material are intermittently applied to the webs. A continuously moving web could be a backsheet web or a topsheet web which is continuously conveyed through a processing line for being severed to form articles of selected lengths, and the conveying mechanisms and supply roll associated with the movement of these web components would generally operate continuously.
Other mechanisms in an absorbent article manufacturing system operate intermittently on a moving web or other component of the article. For example, a pair of tape tabs may be placed at predetermined intervals along a moving web so that each article that is ultimately formed has a pair of properly located tape tabs. Another example of such an intermittent operation is the transverse severing of an assembly of webs so as to separate the individual, completed articles.
Such intermittent processes may be described as "unity operations" which are typically effected relative to at least one associated moving web once per each article. Such a unity operation must be timed and controlled to occur at a precise location on, or relative to, the moving web. The unity operation must thus be controlled relative to the speed of the web.
Further, owing to tolerances in the operating mechanisms, slippage of the absorbent article components along the processing line, etc., precise registration of such unity operations with the moving web or webs is difficult, and becomes especially difficult at high line speeds. Accordingly, it would be advantageous to provide an improved system for effecting unity operations in a controlled manner relative to the continuous operations and relative to actual selected locations on moving webs.
Further, it would be desirable to provide such an improved system with means for efficiently transferring power to a plurality of unity operators in an absorbent article manufacturing line. Also, it would be advantageous to provide such a power transmission system with a design that could accommodate relatively easy installation, service, and adjustment of the mechanisms.
Changing market conditions may require a manufacturer to quickly modify its products or provide new products. Further, flexible manufacturing techniques and programs are nowadays becoming more frequently employed by manufacturers to accommodate, in one manufacturing system, the sequential production runs of a number of different products. To this end, it would be desirable to provide an improved system for an absorbent article manufacturing apparatus which would operate in a way that would more readily accommodate product changes or modifications.
In particular, it would be beneficial if such an improved system could function to mount and support absorbent article manufacturing mechanisms in a manner that would accommodate relatively rapid installation, servicing, and adjustment of such mechanisms.
It would also be desirable for such an improved system to accommodate expansion of the manufacturing line by the addition of mechanisms that would provide alternative or additional features on an absorbent article product.
Further, it would be advantageous if such an improved system could readily accommodate changes in the placement or location of selected mechanisms along the processing line, and such an improved system should preferably require only a minimum number of different support components so as to reduce manufacturing complexity and simplify installation.
The present invention provides an improved absorbent article manufacturing system which can accommodate designs having the above-discussed benefits and features.